1. Field of the Invention
The present invention relates generally to knitted spacer fabric and, more particularly, to three dimensional knitted spacer fabric having integral, exposed loops for hook-and-loop fastener functionality on a predetermined surface of the fabric.
2. Description of the Relevant Art
Prior art includes spacer fabrics and hook-and-loop type fasteners. However, hook-and-loop type fasteners are formed in or cut down to strips of relatively narrow widths and require affixation to fabric, material or other surfaces. Typically this affixation is by adhesive or mechanical stitching or sewing, in the case of fabrics in particular. Delamination or detachment of the affixed sides of the hook-and-loop type fasteners is a common failure mechanism. Additionally, typically the looped side of the hook-and-loop type fasteners deteriorates or wears from use and requires replacement of the strip because the hooked side pulls at this looped surface and degrades the loops. Furthermore, spacer fabric use within the prior art and looped fabric are separate, independent fabrics that are not known to be integrated or formed within the same fabric body; there is simply no known method for forming such an integrated fabric that provides all of the benefits of a spacer fabric with those of a looped fabric. As separate fabrics, the spacer fabric has many applications. The second fabric that is a fabric that has loops knit into the fabric, including brushed or napped loops that provide a soft fleece surface; this surface is used in different applications, including using the fabric as soft surface inside of a garment, as a insulating surface inside of a garment, as a soft surface inside of a sport brace, as a soft surface needed in any application. Additionally, the loops of this second type of fabric may be left unbrushed or as natural loops, and in this case these loops are usually using a heavier denier per filament of yarn and are typically known as the loop fabric in a hook-and-loop fastener combination such as the commercially available VELCRO. These loops function to provide resistance for the hook not to pull loose, as is known in the art. Thus, there is a longstanding and unmet need to combine these two fabric constructions into one integrated fabric. Again, currently there is no known way of making these two unique fabric constructions into one integrated fabric during the same fabric-forming or knitting process. The current combination of these fabrics is only done by laminating the two fabrics together. During the lamination of two fabrics together, the properties of each fabric are changed and diminished due to the adhesion or lamination of the fabrics to each other. This adhesion also affects the inherent stretch in the fabrics and therefore changes their individual and collective properties; it also affects the breatheability of combined fabrics by using adhesives or film. Therefore there continues to be a need to make this fabric during one process.
Examples of relevant art patent documents include the following:
U.S. Pat. No. 5,817,391, “Three-dimensional knit spacer fabric for bed pads”, Rock et al., provides a three dimensional knit or woven fabric with a first layer and a second layer spaced from each other by an interconnecting resilient yarn that is suitable for use in bed pads.
In U.S. Pat. No. 6,116,059, “Three-dimensional sport medical support spacer fabric”, (Rock et al.), is a three dimensional knit spacer fabric with a hydrophilic first layer, an abrasion resistant second layer spaced with a resilient yarn.
In U.S. Pat. No. 6,199,410, “Double face warp knit fabric with two-side effect”, Rock et al. describe a method for making fabric with a velour on one side and a velvet on the other. The two faces may be of different colors.
U.S. Pat. No. 6,755,052, “Knitted stretch spacer material and method of making”, (Sytz) is a knitted spacer material with increased stretch and compression resistance; decreased weight and improved comfort and shape.
In U.S. Pat. No. 5,385,036, “Warp knitted textile spacer fabric, method of producing same, and products produced therefrom” (Spillane et al.) a warp knitted textile spacer fabric is comprised of front and back fabric layers interconnected with monofilament pile yarns. The fabric resists compression and relative shear of the two fabric layers.
In U.S. Pat. No. 5,413,837, “Three dimensional knit fabric”, Rock et al. describe a three-dimensional knit fabric that is permeable to water vapor but impermeable to liquid water.
U.S. Pat. No. 5,783,277, “Three-dimensional knit spacer fabric for footwear and outerwear” (Rock et al.) provides an integrated knit spacer fabric with two fabric layers, both of which are made from hydrophilic fibers.
In U.S. Pat. No. 6,156,406, “Three-dimensional high-low bulk spacer fabric” (Rock et al.) a three dimensional knit fabric with two layers is connected with yarn. In some sections the yarn is perpendicular to the layers while in others it is set at an angle to the layers. The sections with the yarn set at an angle to the layers expand upon application of a pressurized air source.
U.S. Pat. No. 6,644,070 “Three dimensional fabric for seat”, (Ikenaga et al.) is a three dimensional fabric with increased comfort and resistance to compression that make it useful as a seat cover.
In U.S. Pat. No. 6,758,068, “Three dimensionally structured warp knitted fabric”, Shirasaki et al. describe an improved three-dimensional warp knitted fabric. The improvements are achieved by using connecting yarn controlling yarns that limit the deterioration of the fabric.
U.S. Pat. No. 5,735,145, “Weft knit wicking fabric and method of making same” (Pernick) is a multilayer fabric of two hydrophilic layers connected by spacer yarns.
U.S. Pat. No. 6,779,369, “Weft knitted spacer fabrics”, (Shepherd) provides a method of producing a jacquard patterned, weft knitted three dimensional fabric on a double jersey circular knitting machine.
Thus there remains a need in the field for a fabric having integral, exposed loops on a surface that function as hook-and-loop type fastener for the looped side to resolve the typical failures modes present in the relevant art.